Re: Example of a framework?

[Kaelin Colclasure]

On Saturday, January 12, 2002, at 02:36 AM, Nicola Pero wrote:

> > I'm new to GNUstep, so forgive me if I'm asking trivially simple
> > questions. Where might I find a reasonably concise example of how to 
> > set
> > up a makefile, etc. for a framework bundle? And once I have it, is it
> > possible to have it included in a RPM as part of a separate tool? Are
> > tools really bundled at all?
>
> > I'm in the midst of building a benchmarking framework for firewalls, 
> > and
> > most of the functionality is in two tools: fwbcontrol which is run by
> > the operator, and fwbworker which is spawned on all of the test hosts 
> > in
> > a cluster. I would like for these two tools to share a common 
> > framework,
> > yet they must be packaged (in RPMs) separately because they're 
> > installed
> > on different machines. Right now I build a fwbench-control package and
> > an fwbench-worker package. Ideally the common framework would get
> > included in each... However, I would settle for having a third
> > fwbench-common package if that simplifies things significantly.
>
> Well - I suppose you basically have -
>
>  - a shared library (the proper core of your `framework')
>  - two tools both of them using this same library.
>
> the idea with RPMs is that they work the same way as you would use the
> source code ...
>
> so really have two options -
>
>  - either you build a framework containing both the library (as the
>    main framework object) and the two tools, and install the framework
>    with both tools on all machines - that makes a single big RPM;

I'd like to avoid this because I am working with two very differently 
configured classes of machines here -- cluster (worker) nodes and 
workstation (control) hosts. I don't want to be restricted on the 
control side to the set of libraries, etc. available on the workers.

>  - or you build a project containing three subprojects - a framework
>    (or perhaps simply a library if you don't need the special features
>    of frameworks), and the two tools - if you build the RPM from the top
>    level, all the subprojects get automatically included in the RPM;
>
>  - or you have a separate framework project (/library) - which makes
>    up a first RPM you install on both machines - and then you have the
>    two tools as separate projects - which makes other two RPMs, which 
> you
>    can install separately.

This is workable... but my (poorly elaborated) question was really more 
about how bundles work under GNUstep. Let me try to explain in a bit 
more detail...

I have just been reading about bundles in Apple's "Inside Mac OS X: 
System Overview" and I am trying to get a grasp on how / whether the 
same feature set is available from GNUstep. I am reading that an 
application bundle can include a `Frameworks' directory containing 
private frameworks, and that the libraries included there will always be 
used in preference to any other when that application loads a shared 
library. Does GNUstep implement a similar feature? And if so, is it 
supported by GNUstep make? And if so, is there an example GNUmakefile / 
project directory structure that I can crib from?

A related confusion on my part: Are tools considered to be in a bundle 
or not? They do use the nice wrapper script for finding the correct 
executable for the current platform / library combination...

> Having the framework installed with each tool is not as clean, because 
> if
> you want to install both the tools, you end up with the framework
> installed twice.

For most normal uses I would agree completely, but in this specific case 
the wasted disk space and potential for version conflict are not really 
concerns. My priority is that configuring additional machines to act as 
workers is a quick and (relatively) painless process. I also will 
eventually have to deal with machines that don't (natively) do RPM.  Mac 
OS X and OpenBSD sooner, but eventually perhaps even (shudder) Windows.

The ability of a bundle to handle multiple executables (for different 
platforms) seems attractive. But I'm not quite to the point of needing 
to figure that one out just yet.

> Building a framework using gnustep-make should be quite easy ... it's
> basically the same as for a library, with some more options - you can 
> know
> about them by looking at the header of the framework.make makefile
> included by gnustep-make.

Yes, I'm finding GNUstep make to be quite pleasant to work with. Thanks 
for the pointer, I'll check it out and see what I can come up with. :-)

-- Kaelin